Public Class FileStreamFactory 
   Implements CSharpTest.Net.Interfaces.IFactory(Of Stream) 

public class FileStreamFactory : CSharpTest.Net.Interfaces.IFactory<Stream>  

using (TempFile tempFile = new TempFile())
{
    FileStreamFactory factory = new FileStreamFactory(tempFile.TempPath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite);
    using (DisposingList<Stream> open = new DisposingList<Stream>())
    {
        for( int i = 0; i < 50; i++ )
            open.Add(factory.Create());
    }
}

Using tempFile As New TempFile()
    Dim factory As New FileStreamFactory(tempFile.TempPath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite)
    Using open As New DisposingList(Of Stream)()
        Dim i As Integer = 0
        While i < 50
            open.Add(factory.Create())
            System.Math.Max(System.Threading.Interlocked.Increment(i),i - 1)
        End While
    End Using
End Using